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https://www.readbyqxmd.com/read/30517825/colorimetric-detection-of-the-%C3%AE-agonist-ractopamine-in-animal-feed-tissue-and-urine-samples-using-gold-silver-alloy-nanoparticles-modified-with-sulfanilic-acid
#1
Xing Hu, Jiawei Du, Junhui Pan, Fengfeng Wang, Deming Gong, Guowen Zhang
A highly sensitive, selective and simple method was proposed for colorimetric detection of ractopamine on the basis of the interaction between ractopamine and sulfanilic acid-modified gold-silver alloy nanoparticles (AuAgNPs). The AuAgNPs were prepared by the reduction of HAuCl4 and AgNO3 with sodium citrate in aqueous medium and further modified by sulfanilic acid. The interaction of ractopamine with sulfanilic acid induced rapid aggregation of sulfanilic acid-modified AuAgNPs along with an optical colour change, leading to precise quantification which could be detected by absorptiometry...
December 5, 2018: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/30517475/evaluation-of-physicochemical-properties-of-new-calcium-silicate-based-sealer
#2
Aline Teixeira Mendes, Paula Barcellos da Silva, Bruna Barcelos Só, Lina Naomi Hashizume, Rodrigo Ricci Vivan, Ricardo Abreu da Rosa, Marco Antonio Húngaro Duarte, Marcus Vinícius Reis Só
This study aimed to evaluate the physicochemical properties of a calcium silicate-based sealer (Sealer Plus BC; MK Life, Porto Alegre, Brazil) compared with an epoxy-resin sealer (AH Plus; Dentsply DeTrey GmbH, Konstanz, Germany). Initial and final setting time was assessed based on ISO 6876:2012 and ASTM C266:03. Calcium ion release and pH were evaluated by filling polyethylene tubes with sealers and then immersing them in 10 mL of deionized water. Following experimental periods of 1, 24, 72 and 168 hours, the samples were measured regarding pH and calcium ion release with a pH meter and a colorimetric spectrophotometer, respectively...
November 2018: Brazilian Dental Journal
https://www.readbyqxmd.com/read/30517444/antibacterial-efficacy-of-synthetic-and-natural-derived-novel-endodontic-irrigant-solutions
#3
Larissa Tais Soligo, Ediléia Lodi, Ana Paula Farina, Matheus Albino Souza, Cristina de Mattos Pimenta Vidal, Doglas Cecchin
The aim of this study was to compare the efficacy of grape seed extract (GSE), calcium hypochlorite [Ca(ClO)2], and sodium hypochlorite (NaOCl) irrigant solutions with rotary or reciprocating instrumentation for disinfection of root canals inoculated with Enterococcus faecalis. The mesiobuccal root canals of mandibular molars were prepared and inoculated with Enterococcus faecalis for 21 days. The roots were then randomly divided into the following eight experimental groups (n=11) according to the instrumentation technique and disinfection protocol: ProTaper Next or Reciproc R25 with sodium chloride (control group), 6% NaOCl, 6% Ca(ClO)2, or 50% GSE used for irrigation during instrumentation...
September 2018: Brazilian Dental Journal
https://www.readbyqxmd.com/read/30517280/preanalytical-conditions-can-interfere-with-m-tuberculosis-detection-by-pcr-in-respiratory-samples
#4
Gabriela Gaspar Carnevale, Francisco Suso Vargas, Hélio Hehl Caiaffa-Filho, Milena Marques Pagliarelli Acencio, Lia Junqueira Marçal, Roberta Karla Barbosa Sales, Lisete Ribeiro Teixeira, Leila Antonangelo
OBJECTIVES: Tuberculosis is one of the most prevalent infections in humans. Although culture is the reference for diagnosis, its sensitivity is compromised, especially in paucibacillary samples. Because polymerase chain reaction (PCR) amplifies mycobacterial DNA, it is more sensitive than culture for the diagnosis of Mycobacterium tuberculosis (Mtb). However, its performance can be affected by intrinsic sample inhibitors and by the extraction/detection techniques used. METHODS: We evaluated the influence of preanalytical conditions on Mtb detection in samples of sputum (SPU), bronchoalveolar lavage (BAL), and pleural fluid (PF) using combinations of extraction/detection methods...
November 29, 2018: Clinics
https://www.readbyqxmd.com/read/30517195/rapid-and-highly-specific-generation-of-targeted-dna-sequencing-libraries-enabled-by-linking-capture-probes-with-universal-primers
#5
Joel Pel, Amy Leung, Wendy W Y Choi, Milenko Despotovic, W Lloyd Ung, Gosuke Shibahara, Laura Gelinas, Andre Marziali
Targeted Next Generation Sequencing (NGS) is being adopted increasingly broadly in many research, commercial and clinical settings. Currently used target capture methods, however, typically require complex and lengthy (sometimes multi-day) workflows that complicates their use in certain applications. In addition, small panels for high sequencing depth applications such as liquid biopsy typically have low on-target rates, resulting in unnecessarily high sequencing cost. We have developed a novel targeted sequencing library preparation method, named Linked Target Capture (LTC), which replaces typical multi-day target capture workflows with a single-day, combined 'target-capture-PCR' workflow...
2018: PloS One
https://www.readbyqxmd.com/read/30517067/ferrule-design-does-not-affect-the-biomechanical-behavior-of-anterior-teeth-under-mechanical-fatigue-an-in-vitro-evaluation
#6
F E Figueiredo, R C Santos, A S Silva, A D Valdívia, L A Oliveira-Neto, S Griza, C J Soares, A L Faria-E-Silva
OBJECTIVES: To investigate the survival and failure mode of fiber-post resin restorations over preparations with different ferrule designs when submitted to a fatigue load test. METHODS AND MATERIALS: Fifty bovine incisors were selected and divided into five groups (n=10) according to ferrule design: a no-ferrule group, a 2-mm circumferential ferrule group, a 2-mm buccal ferrule group, a 2-mm lingual ferrule group, and a 2-mm buccal and lingual ferrule group. The fiberglass post was cemented and the composite core was built up and prepared, followed by cementation of a full composite crown...
October 10, 2018: Operative Dentistry
https://www.readbyqxmd.com/read/30516959/forensic-analysis-and-differentiation-of-black-powder-and-black-powder-substitute-chemical-signatures-by-infrared-thermal-desorption-dart-ms
#7
Thomas P Forbes, Jennifer R Verkouteren
The trace detection and forensic analysis of black powders and black powder substitutes, directly from wipe-based sample collections was demonstrated using infrared thermal desorption (IRTD) coupled with direct analysis in real time mass spectrometry (DART-MS). Discrete 15 s heating ramps were generated, creating a thermal desorption profile that desorbed more volatile species (e.g., organic and semivolatile inorganic compounds) at lower temperatures (250 °C to 400 °C) and nonvolatile inorganic oxidizers at high temperatures (450 °C to 550 °C)...
December 5, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/30516763/on-the-sensitization-of-eu-3-with-ce-3-and-tb-3-by-composite-structured-ca-2-luhf-2-al-3-o-12-garnet-phosphors-for-blue-led-excitation
#8
Stefan Fischer, Tim Pier, Thomas Jüstel
This work deals with the photoluminescence of various composite structured Ca2LuHf2Al3O12 garnet type LED phosphors. It is well known that sensitization of Eu3+ with Ce3+ suffers from metal-to-metal charge transfer (MMCT) quenching. Spatial separation of the sensitizer and activator results in a reduced quenching mechanism and thus higher luminescence intensities, when Ce3+ is excited in the blue spectral range and transfers its energy to Eu3+. The phosphor particles were prepared via different synthesis techniques...
December 5, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/30516616/performance-characteristics-of-endometrial-sampling-in-diagnosis-of-endometrial-carcinoma
#9
Catalin Taraboanta, Heidi Britton, Anna Plotkin, Nazila Azordegan, Philip B Clement, C Blake Gilks
Outpatient endometrial biopsy can give false-negative results, with a 0.9% reported posttest probability for endometrial carcinoma (EC) after a negative result. Our objective was to determine if there has been any improvement in the performance characteristics of endometrial biopsy over the last 15 yr. All hysterectomy specimens with a diagnosis of EC or atypical hyperplasia (AH), reported between May 2011 and May 2015, were identified and cross-referenced for any negative endometrial sampling results during the 5 yr before hysterectomy...
December 3, 2018: International Journal of Gynecological Pathology
https://www.readbyqxmd.com/read/30516399/source-apportioned-coarse-particulate-matter-exacerbates-allergic-airway-responses-in-mice
#10
Marie McGee Hargrove, John K McGee, Eugene A Gibbs-Flournoy, Charles E Wood, Yong Ho Kim, M Ian Gilmour, Stephen H Gavett
Exposure to coarse particulate matter (PM) is associated with lung inflammation and exacerbation of respiratory symptoms in sensitive populations, but the degree to which specific emission sources contribute to these effects is unclear. We examined whether coarse PM samples enriched with diverse sources differentially exacerbate allergic airway responses. Coarse PM was collected weekly (7/2009-6/2010) from urban (G.T. Craig [GTC]) and rural (Chippewa Lake Monitor [CLM]) sites in the Cleveland, Ohio area. Source apportionment results were used to pool GTC filter PM extracts into five samples dominated by traffic, coal, steel (two samples), or road salt sources...
December 5, 2018: Inhalation Toxicology
https://www.readbyqxmd.com/read/30515855/high-throughput-96-well-solid-phase-extraction-for-preparation-of-tetracycline-followed-by-liquid-chromatography-and-mass-spectrometry-analysis
#11
Kang Chen, Jie Wang, Shiyan Li, Yang Wang, Yiqi Zhang, Qing Shen
Tetracyclines abuse is frequently occurred in aquaculture against bacteria, rickettsiae, spirochetes and mycoplasmas. In this study, a high-throughput sample preparation method was developed using 96-well plate solid-phase extraction (p-SPE) and the extract was anal. yzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The experimental conditions were optimized such that the pH is 4, the eluting solvent is methanol (2 mL), and the sorbent is hydrophilic-lipophilic balance (HLB) microsphere...
December 4, 2018: Electrophoresis
https://www.readbyqxmd.com/read/30515692/residue-behavior-and-risk-assessment-of-cymoxanil-in-grape-under-field-conditions-and-survey-of-market-samples-in-guangzhou
#12
Jianxiang Huang, Qian Ye, Kai Wan, Fuhua Wang
A simple and fast method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for cymoxanil residue analysis in grape. Sample preparation based on solid-liquid extraction was optimized without using adsorbent for purification. Recoveries were 79.8-109.5% with relative standard deviations (RSDs) of 2.5-9.4% at fortified levels from 0.001 to 0.50 mg/kg. The limit of detection (LOD) was 0.3 μg/kg. Field trials were conducted to explore the dissipation and terminal residue behavior of cymoxanil in grape...
December 4, 2018: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/30515570/improved-performance-of-lateral-flow-immunoassays-for-alpha-fetoprotein-and-vanillin-by-using-silica-shell-stabilized-gold-nanoparticles
#13
Xuewen Lu, Ting Mei, Qi Guo, Wenjing Zhou, Xiaomei Li, Jitao Chen, Xinke Zhou, Ning Sun, Zhiyuan Fang
The sensitivity of lateral flow assays (LFA) was increased 30-fold by making use of spherical core-shell gold-silica nanoparticles (AuNP@SiO2 NPs). They can be prepared by silylation of surfactant stabilized AuNPs. The AuNP@SiO2 NPs are highly stable and can be used to label antibodies at virtually any concentration. The detection limit of an LFA for alpha-fetoprotein (AFP) can be decreased from 10 ng·mL-1 to 300 pg·mL-1 which makes it comparable to an enzyme-linked immunosorbent assay. To demonstrate the applicability to an immunoassay, a sandwich assay was developed for vanillin by covalent modification of the AuNP@SiO2 NPs with antibody...
December 4, 2018: Mikrochimica Acta
https://www.readbyqxmd.com/read/30515538/mapping-the-triglyceride-distribution-in-nafld-human-liver-by-maldi-imaging-mass-spectrometry-reveals-molecular-differences-in-micro-and-macro-steatosis
#14
Hussam Alamri, Nathan Heath Patterson, Ethan Yang, Pablo Zoroquiain, Anthoula Lazaris, Pierre Chaurand, Peter Metrakos
Hepatic lipid accumulation, mainly in the form of triglycerides (TGs), is the hallmark of non-alcoholic fatty liver disease (NAFLD). To date, the spatial distribution of individual lipids in NAFLD-affected livers is not well characterized. This study aims to map the triglyceride distribution in normal human liver samples and livers with NAFLD and cirrhosis with imaging mass spectrometry (MALDI IMS). Specifically, whether individual triglyceride species differing by fatty acid chain length and degree of saturation correlate with the histopathological features of NAFLD as identified with classical H&E...
December 5, 2018: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/30515451/conducting-research-with-older-adults-with-vision-impairment-lessons-learned-and-recommended-best-practices
#15
Corinna Trujillo Tanner, Michael S Caserta, Julia J Kleinschmidt, Margaret S Clayton, Paul S Bernstein, Jia Wen Guo
Older adults are underrepresented in research, and a potential barrier to their participation may be the increasing prevalence of vision loss and lack of accommodation for this challenge. Although vision loss may initially pose a challenge to research participation, its effects can be mitigated with early, in-depth planning. For example, recruitment is more inclusive when best practices identified in the literature are used in the preparation of written materials to reduce glare and improve readability and legibility...
January 2018: Gerontology & Geriatric Medicine
https://www.readbyqxmd.com/read/30515007/formulating-telemedicine-strategies-in-isfahan-university-of-medical-sciences
#16
Asghar Ehteshami, Sakineh Saghaeiannejad-Isfahani, Mahnaz Samadbeik, Khdijeh Falah
Introduction: The use of telemedicine technology can lead to an equitable distribution of specialized care. There are numerous influencing factors which should be identified for successful implementation and efficacy of telemedicine. The aim of this study was to evaluate current situation and internal and external environment of Isfahan University of Medical Sciences (IUMS) and prepare telemedicine development strategies for IUMS. Methods: This study was an applied cross-sectional mixed method study which was conducted between July 2014 to November 2016 and in five phases in IUMS...
October 2018: Acta Informatica Medica: AIM
https://www.readbyqxmd.com/read/30514859/green-preparation-and-characterization-of-graphene-oxide-carbon-nanotubes-loaded-carboxymethyl-cellulose-nanocomposites
#17
Yeong-Rae Son, Soo-Jin Park
In this study, a homogeneous and stable dispersion of graphene oxide (GO)/carbon nanotube (CNT) complexes (GCCs) was obtained by dispersing CNTs in an aqueous solution using GO in the absence of dispersing agents. Furthermore, carboxymethyl cellulose/GCC (CMC/GCC) nanocomposite films were prepared by a simple solution mixing-evaporation method. The dispersibility of the GCCs with different CNT contents was investigated by UV-Vis spectrophotometry. The morphological and crystalline structures of the samples were analyzed by transmission electron microscopy, scanning electron microscopy, and X-ray diffraction...
December 4, 2018: Scientific Reports
https://www.readbyqxmd.com/read/30514834/epigenetically-reprogrammed-methylation-landscape-drives-the-dna-self-assembly-and-serves-as-a-universal-cancer-biomarker
#18
Abu Ali Ibn Sina, Laura G Carrascosa, Ziyu Liang, Yadveer S Grewal, Andri Wardiana, Muhammad J A Shiddiky, Robert A Gardiner, Hemamali Samaratunga, Maher K Gandhi, Rodney J Scott, Darren Korbie, Matt Trau
Epigenetic reprogramming in cancer genomes creates a distinct methylation landscape encompassing clustered methylation at regulatory regions separated by large intergenic tracks of hypomethylated regions. This methylation landscape that we referred to as Methylscape is displayed by most cancer types, thus may serve as a universal cancer biomarker. To-date most research has focused on the biological consequences of DNA Methylscape changes whereas its impact on DNA physicochemical properties remains unexplored...
December 4, 2018: Nature Communications
https://www.readbyqxmd.com/read/30514590/a-magnetic-hyperbranched-polyamide-amine-based-quick-easy-cheap-effective-rugged-and-safe-method-for-the-detection-of-organophosphorus-pesticide-residues
#19
Jun Wang, Zhao-Li Mou, Hui-Ling Duan, Shi-Yao Ma, Jing Zhang, Zhi-Qi Zhang
Magnetic hyperbranched polyamide amine (MHPA) was successfully prepared and applied as a QuEChERS adsorbent to the gas chromatograph-mass spectrometer (GC-MS) detection of organophosphorus pesticides (OPPs) in orange juice. Abundant in amino types and the structure of hyperbranched organic chains make MHPA to possess the clean-up function integrating classic clean-up agent primary secondary amine (PSA) with C18 modified silica, and the magnetic property makes the operation easier and more time-saving. Compared the performance with classical clean-up agents of PSA and C18 , better results were obtained with MHPA as adsorbent for the detection of 11 OPPs...
November 27, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/30514484/a-rapid-ultrasonic-energy-assisted-preconcentration-method-for-simultaneous-extraction-of-lead-and-cadmium-in-various-cosmetic-brands-using-deep-eutectic-solvent-a-multivariate-study
#20
Tasneem Gul Kazi, Hassan Imran Afridi, Murk Bhatti, Asma Akhtar
An innovative ultrasonic assisted microextraction method using a deep eutectic solvent for entrapping the organ metallic complexes was developed to pre-concentrate the trace quantities of cadmium (Cd) and lead (Pb) in lipsticks and eye shadows of different brands prior to flame atomic absorption spectrometry analysis. A deep eutectic solvent (DES) was used in this study, prepared by mixing metal salt (ZnCl2 ) and hydrogen bond donors such as (acetamide) in different ratio. The different branded cosmetic items, lipstick and eye shadows, obtained from local market and subjected to acid digestion prior to application of proposed ultrasonic assisted microextraction method based on deep eutectic solvent (UAµE-DES) with the aid of mechanical and ultrasound energies...
March 2019: Ultrasonics Sonochemistry
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