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https://www.readbyqxmd.com/read/29167965/impact-of-suspended-solids-on-the-use-of-luminotox-to-detect-toxicity-of-micropollutants
#1
Meghan Marshall, Marco Pineda, Viviane Yargeau
There is an increasing need for tools to monitor toxicity of contaminants of emerging concern (CECs) in wastewater. The purpose of this work was to assess interferences in the presence of total solids (TS) and total suspended solids (TSS) in the LuminoTox at concentrations typical of those found in municipal secondary effluent (SE) and to evaluate a simple sample enrichment method for increased CEC sensitivity. 4 or 10 µg/L atrazine in different TS concentrations and in corresponding filtrates (TSS removed) exhibited equivalent toxicities...
November 22, 2017: Archives of Environmental Contamination and Toxicology
https://www.readbyqxmd.com/read/29167849/identifying-dna-mismatches-at-single-nucleotide-resolution-by-probing-individual-surface-potentials-of-dna-capped-nanoparticles
#2
Hyungbeen Lee, Sang Won Lee, Gyudo Lee, Wonseok Lee, Kihwan Nam, Jeong Hoon Lee, Kyo Seon Hwang, Jaemoon Yang, Hyeyoung Lee, Sangsig Kim, Sang Woo Lee, Dae Sung Yoon
Here, we demonstrate a powerful method to discriminate DNA mismatches at single-nucleotide resolution from 0 to 5 mismatches (χ0 to χ5) using Kelvin probe force microscopy (KPFM). Using our previously developed method, we quantified the surface potentials (SPs) of individual DNA-capped nanoparticles (DCNPs, ∼100 nm). On each DCNP, DNA hybridization occurs between ∼2200 immobilized probe DNA (pDNA) and target DNA with mismatches (tDNA, ∼80 nM). Thus, each DCNP used in the bioassay (each pDNA-tDNA interaction) corresponds to a single ensemble in which a large number of pDNA-tDNA interactions take place...
November 23, 2017: Nanoscale
https://www.readbyqxmd.com/read/29167394/prion-seeding-activity-and-infectivity-in-skin-samples-from-patients-with-sporadic-creutzfeldt-jakob-disease
#3
Christina D Orrú, Jue Yuan, Brian S Appleby, Baiya Li, Yu Li, Dane Winner, Zerui Wang, Yi-An Zhan, Mark Rodgers, Jason Rarick, Robert E Wyza, Tripti Joshi, Gong-Xian Wang, Mark L Cohen, Shulin Zhang, Bradley R Groveman, Robert B Petersen, James W Ironside, Miguel E Quiñones-Mateu, Jiri G Safar, Qingzhong Kong, Byron Caughey, Wen-Quan Zou
Sporadic Creutzfeldt-Jakob disease (sCJD), the most common human prion disease, is transmissible through iatrogenic routes due to abundant infectious prions [misfolded forms of the prion protein (PrP(Sc))] in the central nervous system (CNS). Some epidemiological studies have associated sCJD risk with non-CNS surgeries. We explored the potential prion seeding activity and infectivity of skin from sCJD patients. Autopsy or biopsy skin samples from 38 patients [21 sCJD, 2 variant CJD (vCJD), and 15 non-CJD] were analyzed by Western blotting and real-time quaking-induced conversion (RT-QuIC) for PrP(Sc) Skin samples from two patients were further examined for prion infectivity by bioassay using two lines of humanized transgenic mice...
November 22, 2017: Science Translational Medicine
https://www.readbyqxmd.com/read/29166766/highly-active-graphene-oxide-supported-cobalt-single-ion-catalyst-for-chemiluminescence-reaction
#4
Jue Wang, Wenhui Zhong, Xiaoying Liu, Tongtong Yang, Fang Li, Qi Li, Weiren Cheng, Chen Gao, Zheng Jiang, Jun Jiang, Hua Cui
Graphene or graphene oxide (GO)-supported metallic nanoparticles and single metal atom as potentially effective cata-lysts for chemical reactions have recently received extensive research interests. However, metal utilization in nanopar-ticle catalysts is limited and metal atoms are readily to drift on graphene surface and consequently form aggregated large particles, making practical applications limited. Here, we report metal ions directly immobilized on GO as a novel GO-supported single-ion catalyst for chemiluminecence (CL) reactions...
November 23, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29166278/interactions-between-plant-derived-oestrogenic-substances-and-the-mycoestrogen-zearalenone-in-a-bioassay-with-mcf-7-cells
#5
Sabine Hessenberger, K Botzi, C Degrassi, P Kovalsky, C Schwab, D Schatzmayr, G Schatzmayr, J Fink-Gremmels
Human and animal diets may contain several non-steroidal oestrogenic compounds which originate either from plants (phytoestrogens) or from fungi that infect plants (mycoestrogens such as zearalenone (ZEN)). Phytoestrogens may compete with ZEN in binding to the oestrogen receptor β and thereby may counteract the oestrogenic activity of ZEN. Using a modified version of the E-screen assay, plant-derived oestrogenic substances were tested for their proliferative or anti-proliferative effect on oestrogen-dependent MCF-7 cells...
September 26, 2017: Polish Journal of Veterinary Sciences
https://www.readbyqxmd.com/read/29165491/fe3o4-aunps-anchored-2d-metal-organic-framework-nanosheets-with-dna-regulated-switchable-peroxidase-like-activity
#6
Bing Tan, Huimin Zhao, Weihao Wu, Xuan Liu, Yaobin Zhang, Xie Quan
Two-dimensional (2D) metal-organic framework (MOF) nanosheets emerging as a new member of the 2D family have received significant research interest in recent years. Herein, we have successfully synthesized 2D copper-based MOF nanosheets with bimetallic anchorage using a facile two-step process at room temperature and ambient pressure, denoted as Cu(HBTC)-1/Fe3O4-AuNPs nanosheets. The as-synthesized 2D bimetallic MOF nanosheets displayed enhanced peroxidase-like activity with relatively high catalytic velocity and affinity for substrates compared with previously reported peroxidase mimics...
November 22, 2017: Nanoscale
https://www.readbyqxmd.com/read/29164865/label-free-dna-assay-by-metal-stable-isotope-detection
#7
Rui Liu, Chaoqun Wang, Yuming Xu, Jianyu Hu, Dongyan Deng, Yi Lv
The interest in label-free bioassays is increasing rapidly because of their simple procedure and direct information of the interaction between the target molecule and the sensing unit. One of the major obstacles in the application of label-free biosensors is the difficulty to produce stable and reproducible optical, electric, electrochemical, or magnetic properties for the sensitive detection of the target molecules. In this work, we demonstrated a label-free DNA assay, by directly measuring the intrinsic 63Cu and 65Cu stable isotopes inside the double strand DNA-templated Cu nanoparticles...
November 22, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29163605/the-verticillium-dahliae-snodprot1-like-protein-vdcp1-contributes-to-virulence-and-triggers-the-plant-immune-system
#8
Yi Zhang, Yuhan Gao, Yingbo Liang, Yijie Dong, Xiufen Yang, Jingjing Yuan, Dewen Qiu
During pathogenic infection, hundreds of proteins that play vital roles in the Verticillium dahliae-host interaction are secreted. In this study, an integrated proteomic analysis of secreted V. dahliae proteins was performed, and a conserved secretory protein, designated VdCP1, was identified as a member of the SnodProt1 phytotoxin family. An expression analysis of the vdcp1 gene revealed that the transcript is present in every condition studied and displays elevated expression throughout the infection process...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/29162470/incorporation-of-metabolic-enzymes-to-improve-predictivity-of-reporter-gene-assay-results-for-estrogenic-and-anti-androgenic-activity
#9
Barbara M A van Vugt-Lussenburg, Rosan Bvan der Lee, Hai-Yen Man, Irene Middelhof, Abraham Brouwer, Harrie Besselink, Bart van der Burg
Identification and monitoring of so-called endocrine-disrupting compounds has received ample attention; both the OECD and the United States Environmental Protection Agency (US EPA) have designed tiered testing approaches, involving in vitro bioassays to prioritize and partly replace traditional animal experiments. Since the estrogen (ER) and androgen (AR) receptor are frequent targets of endocrine disrupting chemicals, bioassays detecting interaction with these receptors have a high potential to be of use in risk assessment of endocrine active compounds...
November 18, 2017: Reproductive Toxicology
https://www.readbyqxmd.com/read/29162457/antiplasmodial-alkaloids-from-bulbs-of-amaryllis-belladonna-steud
#10
Namki Cho, Yongle Du, Ana Lisa Valenciano, Maria L Fernández-Murga, Michael Goetz, Jason Clement, Maria B Cassera, David G I Kingston
A bioassay-guided fractionation and chemical investigation of Amaryllis belladonna Steud. bulbs resulted in the isolation and identification of the new crinane alkaloid 1,4-dihydroxy-3-methoxy powellan (1), along with the 3 known crinane alkaloids 2-4 and the two lycorane alkaloids 5-6. The structures were elucidated by interpretation of combined HR-ESIMS, CD and 2D NMR spectroscopic data. Among these isolated compounds the lycorane-type alkaloid acetylcaranine (5) exhibited strong antiplasmodial activity, while compounds 3 and 4 were moderately active, and compounds 1 and 6 were inactive...
November 11, 2017: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/29162120/a-village-level-cluster-randomized-entomological-evaluation-of-combination-long-lasting-insecticidal-nets-containing-pyrethroid-plus-pbo-synergist-in-southern-mali
#11
Moussa B M Cisse, Djibril Sangare, Richard M Oxborough, Abdourhamane Dicko, Dereje Dengela, Aboubacar Sadou, Jules Mihigo, Kristen George, Laura Norris, Christen Fornadel
BACKGROUND: There is growing concern that malaria vector resistance to pyrethroid insecticides may reduce the effectiveness of long-lasting insecticidal nets (LLINs). Combination LLINs are designed to control susceptible and pyrethroid-resistant mosquito populations through a mixture of pyrethroid with piperonyl butoxide (PBO) synergist. A cluster randomized trial with entomology outcome measures was conducted in Mali to determine the added benefit over mono-treated pyrethroid predecessors...
November 21, 2017: Malaria Journal
https://www.readbyqxmd.com/read/29162113/determination-of-the-residual-efficacy-of-carbamate-and-organophosphate-insecticides-used-for-indoor-residual-spraying-for-malaria-control-in-ethiopia
#12
Delenasaw Yewhalaw, Meshesha Balkew, Josephat Shililu, Sultan Suleman, Alemayehu Getachew, Gedeon Ashenbo, Sheleme Chibsa, Gunawardena Dissanayake, Kristen George, Dereje Dengela, Yemane Ye-Ebiyo, Seth R Irish
BACKGROUND: Indoor residual spraying is one of the key vector control interventions for malaria control in Ethiopia. As malaria transmission is seasonal in most parts of Ethiopia, a single round of spraying can usually provide effective protection against malaria, provided the insecticide remains effective over the entire malaria transmission season. This experiment was designed to evaluate the residual efficacy of bendiocarb, pirimiphos-methyl, and two doses of propoxur on four different wall surfaces (rough mud, smooth mud, dung, and paint)...
November 21, 2017: Malaria Journal
https://www.readbyqxmd.com/read/29161489/effect-of-the-type-and-number-of-washes-in-the-efficacy-of-long-lasting-insecticidal-nets-for-aedes-aegypti-control-in-girardot-colombia
#13
Diana García, Lucas Alcalá, Juliana Quintero, Sebastián Cortés, Helena Brochero, Gabriel Carrasquilla
INTRODUCTION: The use of long lasting insecticidal materials has shown promising results in the control of Aedes aegypti. OBJECTIVE: To evaluate the efficacy of long-lasting insecticidal nets (PermaNet®) for Aedes aegypti control after three washing treatments in the city of Girardot, Colombia. MATERIALS AND METHODS: Standard bioassays were conducted with the nets following the World Health Organization protocols using wild A. aegypti after three washing treatments: (1) Detergent powder, (2) detergent powder and bleach, and (3) bar soap, until completing 20 washes...
March 29, 2017: Biomédica: Revista del Instituto Nacional de Salud
https://www.readbyqxmd.com/read/29160956/photosensitization-of-molecular-oxygen-on-graphene-oxide-for-ultrasensitive-signal-amplification
#14
Xinfeng Zhang, Li Deng, Chengpeng Huang, Jinyi Zhang, Xiandeng Hou, Peng Wu, Juewen Liu
H2O2 and horseradish peroxidase (HRP) are commonly used together in bioassays. HRP is required to accelerate the reaction between a chromogenic substrate (e.g., 3,3',5,5'-tetramethylbenzidine, TMB) and H2O2 and thus amplifies the signal. We herein explore molecular oxygen for enzyme-free and H2O2-free oxidation, while still using the same colorimetric reaction. Restricted by spin selection rules, the ground-state triplet oxygen needs to be converted to the singlet state to oxide TMB. We used phloxine B (PB) as the photosensitizer for its excellent performance and safety...
November 21, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/29160716/-and-ecarlottones-uncommon-chalconoids-from-fissistigma-latifolium-with-pro-apoptotic-activity
#15
Charlotte Gény, Alma Abou Samra, Pascal Retailleau, Bogdan I Iorga, Hristo Nedev, Khalijah Awang, Fanny Roussi, Marc Litaudon, Vincent Dumontet
Four new compounds, (+)- and (-)-ecarlottone (1), (±)-fislatifolione (5), (±)-isofislatifolione (6), and (±)-fislatifolic acid (7), and the known desmethoxyyangonin (2), didymocarpin-A (3), and dehydrodidymocarpin-A (4) were isolated from the stem bark of Fissistigma latifolium, by means of bioassay-guided purification using an in vitro affinity displacement assay based on the modulation of Bcl-xL/Bak and Mcl-1/Bid interactions. The structures of the new compounds were elucidated by NMR spectroscopic data analysis, and the absolute configurations of compounds (+)-1 and (-)-1 were assigned by comparison of experimental and computed ECD spectra...
November 21, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/29160362/potential-of-endophytic-fungi-as-biocontrol-agents-of-duponchelia-fovealis-zeller-lepidoptera-crambidae
#16
R F Amatuzzi, N Cardoso, A S Poltronieri, C G Poitevin, P Dalzoto, M A Zawadeneak, I C Pimentel
This study reports the first assessment of endophytic fungi isolated from strawberry leaves and selection of isolates for the control of Duponchelia fovealis, a new pest of strawberries. A total of 400 strawberry leaves of the cultivar 'Albion' were collected in four commercial farms. Leaves were disinfected, cut in fragments, and placed on Petri dishes containing potato dextrose agar media with tetracycline and incubated for 30 days. Following this time, 517 fungal colonies were isolated, and thirteen genera were identified: Cladosporium, Aspergillus, Nigrospora, Fusarium, Trichoderma, Chaetomium, Alternaria, Paecilomyces, Penicillium, Ulocladium, Bipolaris, Diaporthe, and Phoma...
November 9, 2017: Brazilian Journal of Biology, Revista Brasleira de Biologia
https://www.readbyqxmd.com/read/29159796/host-preferences-of-telenomus-podisi-hymenoptera-scelionidae-parasitism-on-eggs-of-dichelops-melacanthus-euschistus-heros-and-podisus-nigrispinus-hemiptera-pentatomidae
#17
A P Queiroz, E A Taguti, A F Bueno, M L M Grande, C O Costa
Successful biological control requires detailed knowledge about host preferences of the released parasitoid, because the presence of alternative hosts may affect the control of the target pest. The objective of this work was therefore to evaluate host preferences of Telenomus podisi Ashmead among the eggs of three stink bug species: Dichelops melacanthus Dallas, Euschistus heros Fabricius, and Podisus nigrispinus Dallas (Heteroptera: Pentatomidae). Three independent experiments were carried out to study host preferences among the following: (1) E...
November 20, 2017: Neotropical Entomology
https://www.readbyqxmd.com/read/29158352/intracytoplasmic-sperm-injection-state-of-the-art-in-humans
#18
Gianpiero D Palermo, Claire L O'Neill, Stephen Chow, Stephanie Cheung, Alessandra Parrella, Nigel Pereira, Zev Rosenwaks
Amongst infertile couples, 25% involve both male and female factors, while male factor alone accounts for another 25% due to oligo-, astheno-, terato-zoospermia, a combination of the three, or even a complete absence of sperm cells in the ejaculate and can lead to a poor prognosis even with the help of assisted reproductive technology (ART). Intracytoplasmic sperm injection (ICSI) has been with us now for a quarter of a century and in spite of the controversy generated since its inception, it remains in the forefront of the techniques utilized in ART...
November 20, 2017: Reproduction: the Official Journal of the Society for the Study of Fertility
https://www.readbyqxmd.com/read/29157606/high-performance-thin-layer-chromatography-hptlc-direct-bioautography-as-a-method-of-choice-for-alpha-amylase-and-antioxidant-activity-evaluation-in-marine-algae
#19
Snezana Agatonovic-Kustrin, David W Morton
High-Performance Thin-layer chromatography (HPTLC) combined with DPPH free radical method and α-amylase bioassay was used to compare antioxidant and antidiabetic activities in ethanol and ethyl acetate extracts from 10 marine macroalgae species (3 Chlorophyta, 4 Phaeophyta and 3 Rhodophyta) from Blue Lagoon beach (Malaysia). Samples were also evaluated for their phenolic and stigmasterol content. On average, higher antioxidant activity was observed in the ethyl acetate extracts (55.1mg/100g gallic acid equivalents (GAE) compared to 35...
November 14, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/29156987/antiviral-phenolics-from-antenoron-filiforme-var-neofiliforme
#20
Shi-Zhong Ma, Shu-Hua Luan, Ling-Juan Zhu, Xue Zhang, Xin-Sheng Yao
Two new phenolics, 1,3-di-O-p-coumaroyl-2',6'-di-O-acetylsucrose (1) and quercetin 3-O-β-D-apiofuranoyl-(1→2)-α-L-rhamnopyranoside (2), along with nine known compounds (3-11), were isolated from the whole plants of Antenoron filiforme var. neofiliforme. Their chemical structures were characterized on the basis of various spectroscopic techniques. This is the first report of the isolation of phenylpropanoid sucrose (1, 3-4) from the genus Antenoron. The bioassay results showed that compound 11 exhibited antiviral activity against the Coxsackie virus B3 (CVB3)...
November 21, 2017: Journal of Asian Natural Products Research
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